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, 13 (2), 188-93

A Randomized, Placebo-controlled Trial of Digestive Enzymes in Children With Autism Spectrum Disorders


A Randomized, Placebo-controlled Trial of Digestive Enzymes in Children With Autism Spectrum Disorders

Khaled Saad et al. Clin Psychopharmacol Neurosci.


Objective: There is growing evidence for a gut-brain connection associated with autism spectrum disorders (ASDs). This suggests a potential benefit from introduced digestive enzymes for children with ASD.

Methods: We performed a double-blind, randomized clinical trial on 101 children with ASD (82 boys and 19 girls) aged from 3 to 9 years. ASD patients were diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders 4th edition, text revision (DSM-IV-TR) diagnostic criteria. Structured interviews of at least one hour each both with the parents and the child were performed. Later on, another two hours-session was conducted applying the Childhood Autism Rating Scale (CARS). ASD patients were randomized to receive digestive enzymes or placebo.

Results: The ASD group receiving digestive enzyme therapy for 3 months had significant improvement in emotional response, general impression autistic score, general behavior and gastrointestinal symptoms. Our study demonstrated the usefulness of digestive enzyme in our population of ASD patients.

Conclusion: Digestive enzymes are inexpensive, readily available, have an excellent safety profile, and have mildly beneficial effects in ASD patients. Depending on the parameter measured in our study, we propose digestive enzymes for managing symptoms of ASD. Digestive enzyme therapy may be a possible option in treatment protocols for ASD in the future.

Keywords: Autism spectrum disorders; Child; Clinical trial; Digestive enzymes.

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